Conventionally, a peristaltic infusion pump is mainly used as a medical infusion pump for feeding a medicinal solution or the like in an infusion tube, in which a door is openably and closably provided to an infusion pump body having a pump mechanism.
The peristaltic infusion pump has a structure for performing feed, in which a plurality of fingers provided to a pump body perform reciprocating motion with individual phases to be in a peristaltic movement as a whole, so that infusion tubes disposed between the fingers and a receiving plate provided to the door are sequentially pressed toward a downstream so as to perform the feed. An example of the peristaltic infusion pump is disclosed in Japanese Patent Application Publication No. S-277183.
In such an infusion pump, if the infusion tube is not fitted at a correct position, when a door provided to the infusion pump is closed so as to perform infusion, an amount of a fed solution is greatly reduced, or any amount of the solution is not fed. Therefore, an infusion pump having a function of detecting a misloaded state of the infusion tube to prevent the misload of the infusion tube is desired.
As an example of an infusion pump having a function of preventing misload of the infusion tube, a technique of detecting the misload of the tube by using a position detection sensor such as a pressure sensitive sensor to control an alarm about abnormal fitting is disclosed in Patent Document 2.
According to the function of preventing misload of the infusion tube in the infusion pump disclosed in Japanese Patent Application Publication No. S-15589, the misfit state of the infusion tube is correctly detected, and the alarm is issued based on the detection, so that the misfit state can be speedily released for a proper and prompt response. Therefore, the infusion pump has a good safety as a medical instrument.
According to a conventional method of detecting misload of an infusion tube by using a position detection sensor, the sensor may be expensive, an output of the sensor needs to be adjusted, or software for electrical control needs to be developed. Therefore, the infusion pump may become expensive.
In order to implement an inexpensive infusion pump maintaining safety, it is preferable to provide a means for detecting misload of an infusion tube.
In order to solve the problems, the present invention according to claim 1 provides a tubing misload detection mechanism for an infusion pump comprising a door, an inner door, and an interlocking part.
The door is supported with a shaft by a pump body of the infusion pump in an openable/closable state; the inner door is supported with a shaft by the door; and when the infusion tube fitted in the pump body presses the inner door, the inner door is moved due to the pressing of the infusion tube.
In the tubing misload detection mechanism for an infusion pump, the interlocking part operates in interlock with the inner door, so that the door is prevented from being stably held in the pump body.
In the tubing misload detection mechanism for an infusion pump, the interlocking part is disposed to a handle provided to the door in the tubing misload detection mechanism for an infusion pump.
The door can be locked with the pump body by inserting a claw portion provided to the interlocking part into a through-hole provided to the pump body.
In the tubing misload detection mechanism for an infusion pump, when the interlocking part operates in interlock with the movement of the inner door, the claw portion of the interlocking part is moved, so that the door is prevented from being stably held in the pump body.
In the tubing misload detection mechanism for an infusion pump, the interlocking part is disposed inside the door in the tubing misload detection mechanism for an infusion pump.
The interlocking part has a prismatic-column-shaped or circular-column-shaped protrusion portion, the protrusion portion is disposed inside the door, and the interlocking part operates in interlock with the movement of the inner door.
In the tubing misload detection mechanism for an infusion pump, the protrusion portion protrudes to an outside of the door and to a position in a pivotable range where the operation of the handle provided to the door is prevented, so that the door is prevented from being stably held in the pump body.
According to the invention, when the infusion tube is misloaded, a manipulator can visually identify the state that the door is not entirely closed, so that the misloaded state of the infusion tube can be detected.
Since the misloaded state of the infusion tube can be detected by using a mechanical structure without use of an electrical position detection sensor, the misloading of the infusion tube can be detected irrespective of abnormality of sensitivity of a sensor due to a use environment or electrical problems such as disconnection of electrical wire lines.
Since conventional expensive sensor or electrical circuits are not needed, a task or facility for adjusting sensitivity of sensor in a production process for the infusion pump is not needed, so that it is possible to implement a tubing mislead detection mechanism for an infusion pump at a low cost with a safety maintained.
Further, since a force exerted from an inner door can be directly exerted on the interlocking part, it is possible to implement a tubing mislead detection mechanism for an infusion pump with a simple structure.
In addition to implementation of the mislead detection mechanism at a low cost, a protrusion portion which is provided to a position where the operation of the handle is prevented is suitable. Therefore, the invention can be applied to any types of handles including handles having various shapes or handles having no lock mechanism.
Hereinafter, tubing misload detection mechanisms for an infusion pumps according to preferred embodiments of the present invention will be described with reference to the accompanying drawings. In the embodiments, the same elements are denoted by the same reference numerals.